You have some kind of a visitor, that's for sure.

A trail cam would work. They can take stills or short movies. They range in price -- the higher end can send you info via the wifi for a subscription fee.

My first thought is raccoons. I remember when I was still living with my parents the doorbell would sometimes ring in the middle of the night but there was nobody at the door. Finally after a heavy rain there were muddy paw prints on the brick of the house and we realized it was raccoons.

Hmmm. I can't imagine a critter is doing it as there's no food about to attract anyone near the door and the keypad is 5' up.

For your own peace of mind you need a camera. I agree with the raccoons as they can climb. Are very curious. Will search any and everything for food. They can open doors and latches, lost chickens when I was a child because they found out how to open a slip latch.

I currently have raccoon tracks on the middle of my back storm door where they climbed the wall then slid along the bar trying to get in.

Get cameras and put your mind to rest. DH bought ours from a company called Defender. Easy to install and it records when activated. There were cameras and a monitor. Very easy system but there are tons of them out there.

Dress in black and go to your neighbor's house late tonight. Take a flashlight. I think you'll find that their keypad is missing a cover and they've been coming over trying to lift yours.

I wouldn't worry about it.

I had a pet raccoon with I was 7-8 years old, and he was very good at unlatching things. We had him latched in an old chicken coop (which was quite spacious for a single raccoon, but he unlatched that, climbed up the wall to my bedroom window, tore through the screened window, unlatched the window, and climbed into my bedroom to be with me. After that, I kept him in the house.

Definitely get a camera and a deer one makes sense. Sounds more like someone is trying to get into your garage. I would rather know who or what it is.

If you have some epoxy glue at home, you could secure it using that and be sure you won't find it open in the future.

Get a fake nasty looking spider and plant it inside the cover; if you hear a scream, you'll catch your culprit, lol. My cover gets earwigs for some reason (garage is not attached to house), so I always have to step back when I open it as they tend to abandon ship when I open it. I wonder if a bird could be opening it looking for bugs. Along with the shiny ring you found, maybe crows or magpies?

I use this brand and a model similar to this. (The one I have has been discontinued) Game Camera

If someone has been trying to get into your garage, it would mean that they are trying number combinations on the keypad. If you and your husband don't use the keypad, why not put some "stuff" on the surface of the keys, so you can tell at a glance if they have been touched?

I love my doorbell camera. I’ve caught a fox sitting on my doormat as well as a raccoon and two cats. I also see who is walking their dog across my lawn. Definitely get a camera. You’ll be surprised by what’s going on out there as well as catching your culprit in the act.

I remember your skull ring incident..........but I did want to mention that our garage key pad also seems to flip up and I really don't think there is anything beyond a possible wind that's doing it. We rarely use it, and maybe once or twice a month will notice that the cover is up.

Our cover flips if the wind is strong enough from the right direction.

Do you have snow? Maybe don’t shovel and look for footprints. Or leave some powder (cornstarch?) on the driveway by it and see if there are footprints?

Do you have a motion-sensor light by the garage? That might help, or the deer-sensor-water-sprayer!

Something like this might solve the mystery and bring peace of mind; https://smile.amazon.com/gp/product/B07W7G23ZG

I have a game camera but I haven't used it much. I bought it to see what was eating my mangoes. And to strap to a tree when camping in bear country to see if I had visitors. If I bought another I'm make sure I could retrieve videos wirelessly.

Interesting about the wind...we have had several really blustery days. While the keypad is in a fairly protected area, it is prone to gusts as evidenced by the show drifts that pile up in front of the garage....

That might just answer the mystery.

I'll have to note when we see it up and the weather conditions.

As DH mentioned, if someone were trying to break in with our keypad, wouldn't they be smart enough to put the cover back down so as not to be detected?

Raccoons like playing with shiny things, it is possible that the keypad is entertainment.

My DH did the same thing. Camera's are sooo cheap now for $30 you can get a set of cameras,, place them outside/inside and motion will send a signal to your phone. We were having issues with bats and mice and wanted to know where/how they were getting in.

<I have a game camera but I haven't used it much. I bought it to see what was eating my mangoes.>

I found out that teenage surfers were eating my mangoes, but I learned this from my next door neighbor.

Do any of your close neighbors have young children? Maybe they are coming over and messing with stuff. Children seem to not have a lot of respect for boundaries these days. It would not be surprising if they are out playing and messing with stuff.

If you put up a camera, try and camouflage it! I would be dying to know what was messing with my stuff. My neighbor has cameras all over his property and has seen several times, people trying to get into his stuff! Not clear enough to identify anyone though, it's usually at night.

No we don't have any young kids in the neighborhood and our neighborhood is very quiet and everyone does a good job of respecting boundaries. We've not had any issues that way that we know of.

I'm thinking the wind might be the answer as it has been windy enough some days to blow the tarps off the woodpiles which are anchored with bricks.

But weird in that we've been here 10 yrs and never noticed it as an issue before.

I’d get the camera. Peace of mind, plus entertainment value. All sorts of cute animals caught strolling by. I hope you get one and it’s just a mischievous raccoon!

A deer/wildlife camera can be very useful. One with very good resolution and mounted to view strategic points can be effective, and also somewhat camouflaged if you have a nearby tree to strap it to. Be careful of the settings as a video will use up a lot of battery life.

If it is wind, it may be the cover has worn and weakened enough over time to make it easier to be moved.

Lars, you have much more interesting wildlife than we have. We just have squirrels.

Put a bit of tape over the cover to see if it’s wind.

Yes socks, I was thinking of using a dot of velcro to keep the lid shut and see what happens...

Ours has been lifted by wind, but not often.

We learned we have deer (of course) The local Elk herd makes it over here-very unexpected as we are a fair way from the river where they hang, we have a resident Bobcat and weasels-two kinds. Neighbor cats as well. Spiders love the camera's infrared lights and moths. Aggravating. None of the raccoons or skunks seem to hang around the cameras. Those are the ones with power instead of batteries. I think DH has stopped using the battery powered game cams. They were installed for security but the word must be out. No people.

Annie, the wind flips up the keypad for my garage door. I see that's been mentioned already, but just wanted to throw more evidence behind that theory.

Those covers are really light and it doesn't take much of a gust to flip them up. My garage faces due East, the keypad itself is tucked into a protected alcove - and I don't even get any wind gusts from that direction - but the wind does crazy stuff and flips that cover up at least a couple times a year.

We so rarely use the keypad that I keep meaning to weigh in down somehow...and then promptly forget until the next time it happens. :)

Solar charged motion detector lights are a good investment and cheaper and easier to set up than cameras. I bought 6 to mount up on our driveway fence to pop on whenever someone or a critter walks up the driveway. Lights are a good deterrent to the curious as they don't know if the lights are hooked up to a camera or other alert devices. Several deigns to choose from on Amazon and they come as cheap as $5 each.

Hopefully, it's nothing. Do the camera for fun. We haven't added a camera yet, but we got a ring doorbell. Interesting to note how many times we've been visited by stray cats. We found coyote poop on both sides of our house. We only live on a ~.25 acre lot with neighbors on all sides. It's action packed out there.

But weird in that we've been here 10 yrs and never noticed it as an issue before.

A lot of changes can happen in 10 years. Sheds get built, garages taken down or built, trees trimmed or taken down or grow taller& wider, hedges planted or removed, fences built-things that can change the wind patterns around your house.

Thanks ci_lantro, but none of those things have happened to change things around our house.